Vegetarian moms-to-be are more likely to give birth to girls than their meat- and fish-eating counterparts, a new study has found.

“We were very surprised,” said Pauline Hudson, part of the team of research scientists at Britain’s Nottingham University that studied the impact of a pregnant woman’s diet on the gender of her child.

“It wasn’t just a fluke. This was something we were never looking to find. We were monitoring the health incomes in vegetarian and nonvegetarian mothers, looking at things like hemoglobin levels,” Hudson said yesterday.

The researchers theorized that a strict vegetarian diet places stress on a woman’s body, meaning that female embryos, which are known to be stronger, survive, while males don’t. They also theorize that such a diet changes the acidity of vaginal secretions, triggering a hostile environment for sperm carrying male DNA.

They also said a vegetarian diet contains chemicals that mimic the movement of female sex hormones, including estrogen.

In the study, the ratio of boys and girls born to vegan mothers in Britain was 81 to 100, compared with the national average of 106 boys for every 100 girls.

Critics, including some of the country’s most prominent vegetarians, panned the study as a “fluke.”

Joan Adler, co-owner of the famed vegetarian Moosewood Restaurant in upstate Ithaca, said it’s baloney to think that a diet consisting wholly of vegetables, fruit and grains would produce more female births.

“I don’t know of any relationship between being vegetarian and the gender of a child,” she said.

“It is a very interesting concept – and I’m all for it. It would be great, especially for our business.”

Samantha Heller, senior clinical nutritionist at NYU Medical Center, was also skeptical, noting the baby’s gender is determined by the father.

“We really don’t know whether being a vegetarian can increase the chances of giving birth to girls. This could just be a fluke. They should have observed what the men were eating at the time of conception,” she said.

The survey was based on the 5,942 pregnant women at Nottingham’s City Hospital in 1998.

Previous studies have found that diets rich in calcium, magnesium and potassium will increase the chances of giving birth to a boy.